Monday, December 14, 2015

Reading List: Rocket Ranch

Many books have been written about Project Apollo, with
a large number devoted to the lunar and Skylab missions,
the Saturn booster rockets which launched them, the Apollo
spacecraft, and the people involved in the program. But
none of the Apollo missions could have left the Earth without
the facilities at the Kennedy Space Center (KSC) in Florida
where the launch vehicle and space hardware were integrated,
checked out, fuelled, and launched. In many ways, those
facilities were more elaborate and complicated than the
booster and spacecraft, and were just as essential in
achieving the record of success in Saturn and
Apollo/Saturn launches. NASA's 1978 official history
of KSC Apollo operations,
Moonport
(available
on-line for free),
is a highly recommended examination of the design
decisions, architecture, management, and operation
of the launch site, but it doesn't delve into the
nitty-gritty of how the system actually
worked.

The present book, subtitled “The Nuts and Bolts
of the Apollo Moon Program at Kennedy Space Center”
provides that detail. The author's research involved reviewing
more than 1200 original documents and interviewing more
than 70 people, most veterans of the Apollo era at KSC
(many now elderly). One thread that ran through the interviews
is that, to a man (and almost all are men), despite what they
had done afterward, they recalled their work on Apollo, however
exhausting the pace and formidable the challenges, as a high
point in their careers. After completing his research, Ward
realised he was looking at a 700 page book.
His publisher counselled that such a massive tome
would be forbidding to many readers. He decided to separate
the description of the KSC hardware (this volume) and the
operations leading up to a launch (described in the companion
title,
Countdown to a Moon Launch,
which I will review in the future).

The Apollo/Saturn lunar flight vehicle was, at the time, the most complex
machine ever built by humans. It contained three rocket stages
(all built by different contractors), a control computer, and
two separate spacecraft: the command/service modules and lunar module,
each of which had their own rocket engines, control thrusters,
guidance computers, and life support systems for the crew. From
the moment this “stack” left the ground, everything had
to work. While there were redundant systems in case of some
in-flight failures, loss of any major component would mean the
mission would be unsuccessful, even if the crew returned safely
to Earth.

In order to guarantee this success, every component in the
booster and spacecraft had to be tested and re-tested, from the
time it arrived at KSC until the final countdown and launch.
Nothing could be overlooked, and there were written procedures
which were followed for everything, with documentation of each
step and quality inspectors overseeing it all. The volume of
paperwork was monumental (a common joke at the time was that
no mission could launch until the paperwork weighed more than
the vehicle on the launch pad), but the sheer complexity
exceeded the capabilities of even the massive workforce and
unlimited budget of Project Apollo. KSC responded by
pioneering the use of computers to check out the spacecraft
and launcher at every step in the assembly and launch process.
Although a breakthrough at the time, the capacity of these
computers is laughable today. The computer used to check out
the Apollo spacecraft had 24,576 words of memory when it
was installed in 1964, and programmers had to jump through
hoops and resort to ever more clever tricks to shoehorn the
test procedures into the limited memory. Eventually, after
two years, approval was obtained to buy an additional 24,000
words of memory for the test computers, at a cost of almost
half a million 2015 dollars.

You've probably seen pictures of the KSC firing room during
Apollo countdowns. The launch director looked out over a
sea of around 450 consoles, each devoted to one aspect of
the vehicle (for example, console BA25, “Second stage
propellant utilization”), each manned by an engineer
in a white shirt and narrow tie. These consoles were connected
into audio “nets”, arranged in a hierarchy
paralleling the management structure. For example,
if the engineer at console BA25 observed something outside
acceptable limits, he would report it on the second stage
propulsion net. The second stage manager would then raise the
issue on the launch vehicle net. If it was a no-go item, it
would then be bumped up to the flight director loop where a
hold would be placed on the countdown. If this wasn't complicated
enough, most critical parameters were monitored by launch
vehicle and spacecraft checkout computers, which could
automatically halt the countdown if a parameter exceeded
limits. Most of those hundreds of consoles had dozens of
switches, indicator lights, meters, and sometimes video
displays, and all of them had to be individually wired to
patchboards which connected them to the control computers or,
in some cases, directly to the launch hardware. And every one
of those wires had to have a pull ticket for its installation,
and inspection, and an individual test and re-test that it was
functioning properly. Oh, and there were three
firing rooms, identically equipped. During a launch, two
would be active and staffed: one as a primary, the other as
a backup.

The level of detail here is just fantastic and may be overwhelming
if not taken in small doses. Did you know, for example, that in
the base of the Saturn V launch platform there was an air conditioned
room with the RCA 110A computer which checked out the booster? The
Saturn V first stage engines were about 30 metres from this
delicate machine. How did they keep it from being pulverised
when the rocket lifted off? Springs.

Assembled vehicles were transported from the Vehicle Assembly
Building to the launch pad by an enormous crawler. The crawler
was operated by a crew of 14, including firemen stationed
near the diesel engines. Originally, there was an automatic
fire suppression system, but after it accidentally triggered
and dumped a quarter ton of fire suppression powder into one
of the engines during a test, it was replaced with firemen. How
did they keep the launcher level as it climbed up the ramp to
the pad? They had two pipes filled with mercury which ran diagonally
across the crawler platform between each pair of corners. These
connected to a sight glass which indicated to the operator if the
platform wasn't level. Then the operator would adjust jacking
cylinders on the corners to restore the platform to level—while
it was rolling.

I can provide only a few glimpses of the wealth of fascinating
minutæ on all aspects of KSC facilities and operations
described here. Drawing on his more than 300 hours of
interviews, the author frequently allows veterans of the
program to speak in their own words, giving a sense of what
it was like to be there, then, the rationale for why
things were done the way they were, and to relate anecdotes
about when things didn't go as planned.

It has been said that one of the most difficult things NASA did
in Project Apollo was to make it look easy. Even space buffs
who have devoured dozens of books about Apollo may be startled
by the sheer magnitude of what was accomplished in designing,
building, checking out, and operating the KSC facilities
described in this book, especially considering in how few years
it all was done and the primitive state of some of the technologies
available at the time (particularly computers and electronics).
This book and its companion volume are eye-openers, and only
reinforce what a technological triumph Apollo was.